In Virginia's US Senate race, Democrat Tim Kaine isn't Barack Obama, and Republican George Allen isn't Mitt Romney or the House GOP leadership. But you wouldn't know it from the special-interest ads pouring into this key battleground state.

Republican GOP candidates former Sen. George Allen, left, listens as E.W. Jackson, a minister from Chesapeake, talks during their debate, Saturday, in Roanoke, Va., with Del. Bob Marshall, second from right, and co-tea party leader for Virginia Jamie Radtke.

"Reckless spending, red ink, higher taxes – [Mr. Kaine and President Obama] have a lot in common," intones ads created by Republican super group Crossroads GPS. Kaine's likely foe, former US senator and former Virginia governor George Allen (R), has put up billboards calling Kaine "Obama's Senator. Not Virginia's."

"It's time we reject this type of divisive politics," says Kaine, a former Virginia governor himself, in a fundraising e-mail. "If you want a Senator who'll partner with the President to do what's best for the nation, I'm your guy."

In Virginia in 2012, presidential politics is perhaps more tightly coupled to senatorial politics than anywhere else in the nation.

The race for the White House always affects contests lower on the ticket. But the Senate contest in Virginia is going to be a battle where presidential questions – What is the legacy of "Obamacare"? Who can cut the federal budget, and where? Will the Republican candidate be conservative enough for the party's restive base? – will not just weigh heavy on the debate: They very well may be the debate, leaving both Mr. Allen and Kaine in the wake of presidential forces far beyond their control.

"They both realize that the national overlay on this election has an impact that may go far beyond what each of them can do in their campaigns," says Bob Holsworth, a Richmond-based consultant who has worked with Virginia governors of both parties.

Consider: Of the 10 US Senate races considered to be the most competitive, only one other contest – Nevada – is in a swing state. Both campaigns and independent analysts believe that is leading, already, to a massive infusion of outside money and attention unmatched in the commonwealth's recent political history.

(Kaine offered Allen a deal whereby both candidates would work to ensure that outside groups buying ads in Virginia would have to disclose their donors. Super political-action committees, which can raise unlimited amounts of money but cannot coordinate directly with political campaigns, are not legally bound to disclose such information. Allen declined the offer. Both campaigns have associated super PACs, although Kaine’s group says it will disclose the names of its donors.)

And it's not just advertising space that's going to be jammed, with Virginia political observers expecting the state to be packed with staff from both presidential campaigns.

“By election day, the Obama campaign will dwarf the Virginia Democratic Party itself and its infrastructure,” says Quentin Kidd, a professor at Christopher Newport University and a Virginia political pollster. “Your ability as Tim Kaine, US Senate candidate, no matter how well positioned you are, you aren’t well positioned enough to dominate the agenda that the Obama campaign is going to impose on Virginia. And I assume the Romney campaign is going to try to do the same thing.”

Just consider how much presidential attention Virginia has received at even this early hour. When Mr. Obama elected to formally inaugurate his general election campaign, his campaign wedded kickoff events in perpetual battleground Ohio to one in Richmond, Va., the city where Kaine was once mayor. After first lady Michelle Obama scheduled a commencement address at Virginia Tech, one of the state's largest universities, GOP presumptive nominee Mitt Romney quickly countered with a graduation speech of his own at nearby Liberty University, the institution founded by late religious right stalwart Jerry Falwell.

Next, nowhere outside of Massachusetts do a pair of Senate candidates have such sizable national profiles to compliment their deep in-state roots. Kaine is a former mayor of Richmond and state lieutenant governor, as well as former governor. He went on to chair the Democratic National Committee and was widely thought to have been on Obama's vice-presidential short list in 2008.

Allen is connected to a football dynasty with Virginia's beloved Washington Redskins: His father was a revered Redskins head coach, and his brother is the team's current general manager. He served for nine years in the Virginia House of Delegates, a term in the US House of Representatives, and a term in the US Senate. He was widely touted as a presidential candidate before coming up some 9,000 votes short in his Senate reelection race against heavy underdog Jim Webb (D) in 2006.

As such, Virginia voters already have well-formed opinions of both candidates, meaning it will be harder for either one to change a voter’s perception. Neither candidate is likely to make a massive, campaign-altering gaffe along the lines of Allen’s “macaca” moment from 2006, an off-the-cuff remark to a Webb campaign staffer, viewed as racially insensitive, that likely cost Allen his razor-thin race against Mr. Webb.

“I don’t see either one of these guys really pushing the other one on the issues,” Mr. Kidd says. “They’re both great debaters. They’re both in command of the issues, they both have a history in Virginia, they’re really well known. There’s nothing one candidate can leverage against the other one, that I can see.”

How are both candidates attempting to harness that national energy? Allen, whose campaign did not respond to requests to make him available for this article, appears more willing to ride national themes, while Kaine is taking a more oblique approach.

Mr. Holsworth, who says he has spoken to Allen on this topic, says Allen is keenly aware of the campaign he’d like to run, a point-by-point contrast with Kaine on a variety of issues. But because of the volume of outside messages his campaign will compete with, he will likely “focus on those issues that are likely to tie into what the voters are going to be thinking about, and a lot of that is the Obamacare, the energy issues," Holsworth says. "It’s going to be related to a smaller set of issues."

Allen’s “Blueprint for America” gives a nod to several Republican touchstones that are likely to play a role in this year’s election season. For example, the plan promises to roll back federal spending to 2008 levels, a key promise of the Pledge to America signed by nearly all congressional Republicans in 2010. It also offers support for an amendment to the US Constitution requiring the federal government to balance its budget, a proposal endorsed by Mr. Romney.

On the stump, Allen talks about lowering energy prices, repealing Obama's signature health-care law, and jump-starting the economy by cutting taxes and government regulation.

"Washington may think we need more big government programs like Obamacare. But Virginians know Obamacare is not, quote, a great achievement," Allen said. “It’s a major impediment to small businesses hiring while health-care costs are going up.”

Kaine, on the other hand, is less rhetorically driven by the national political dialogue. His economic plan bears many marks of national Democratic priorities – the importance of alternative energy and the need for both higher taxes and spending cuts to balance the federal budget, for starters. But at a recent Richmond gala, he also emphasized Virginia's success in overcoming racial segregation and gender inequality in the past half-century, as well as its success in embracing immigration and investing in education at all levels to attract talented workers and companies to the area.

“The key is grow your talent, attract talent, and then you’ll attract the institutions that want to be around talent – and that, to me, is what we need to do at the national level,” Kaine said in a subsequent phone interview.

“Talent” is a framework that lets Kaine touch on several headline national concerns – taxation and economic competitiveness, immigration policy, and women’s issues, to name three – while keeping the discussion anchored in Virginia.

No matter the path the candidates take to lay out their policy agendas, however, each is opting to ride the national arguments in his critique of the other, attempting to tar his opponent with being part of the worst elements of their respective national parties.

Kaine has assumed what Holsworth calls the “tea party critique” of Allen’s time in the Senate and in the governor’s mansion: While calling himself a small-government conservative, Allen nonetheless presided over increases in spending at both the state and federal levels.

“I am a governor who left office with a smaller general fund budget than when we started,” Kaine says. In the Senate, “there have to be some hard decisions made about cuts and a lot of people talk it but they’ve never done it.... Again and again when there were hard decisions to make, the decision that [Allen] made was to dramatically increase spending. He’s running again as a small-government conservative and, well, Virginians got fooled twice; I don’t think they’re going to get fooled again.”

Kaine also criticizes Allen as part of a Republican "war on women," as national Democrats have dubbed it. The Kaine campaign cites issues ranging from Allen's support for a "personhood" bill in the Virginia statehouse – legislation that would have defined life as beginning at conception – to his promise to vote against federal funding for Planned Parenthood and his silence on another Virginia bill that would have required women seeking abortions to undergo invasive ultrasound procedures.

“There’s a sort of double effect of these issues,” Kaine says. Not only do they distract from key economic problems, “but they’re also the issues most likely to divide us at a time when most Virginians strongly feel like we need to do more unifying than division," he adds.

On the other hand, the Allen camp frequently refers to “Chairman Kaine” in a bid to tie him directly to his tenure as the head of the Democratic National Committee during the passage of health-care reform, among other issues. Allen’s attack on the “chairman” also attempts to cleave Kaine from his longtime friend and political mentor, US Sen. Mark Warner (D) of Virginia. A former Virginia governor, Senator Warner is a popular figure in the commonwealth for his mix of fiscal conservatism, business bona fides, and center-left political perspective.

Allen will argue that Kaine is not "Mark Warner’s younger brother,” but rather "the first cousin of [House Democratic leader] Nancy Pelosi and [Senate majority leader] Harry Reid," Holsworth says.

"[Kaine] had a job where his duty was to defend anything and everything that the Democrats in Washington produced as an idea or a policy, and you can be certain that Republicans are going to deal with that," he adds.

Of course, there’s another side to both stories. In Allen’s case, it’s true that government spending went up, while Kaine can consistently point to trimming state outlays. But Allen’s tenure in the governor’s mansion was “extraordinary,” as Holsworth put it, for its policy achievements, including parole and welfare reforms and statewide education exams.

But “because he governed in good times, he spent a lot,” Holsworth notes. Kaine, who faced a massive national economic downturn during his governorship, had no such luxury.

“I don’t think this has anything to do with the respective ideological stances of these two. If you’re governor and the state’s taking in money, you spend it, and if its not taking in money you’re constitutionally bound to balance the budget – so you cut,” Holsworth says.

In Kaine’s case, his temperament and political leanings are closer to Senator Warner’s than they are to Pelosi’s. Kaine is personally anti-abortion, for example, and his defense of the 201o federal health-care law is far short of an ideological tirade. He argues that popular provisions deserve to be protected, such as free preventative care for seniors, the end of insurance companies denying patients coverage for preexisting conditions, and the ability for young Americans to stay on their parents' health-care insurance policy until age 26.

“I recognize that it’s controversial. In Virginia, my sense is that it’s about even between people who would like to repeal and people who would like to keep it in place and make it better,” Kaine says. “If you ask people, ‘What do you think, should we kick kids off their family insurance policy in that 21- to 26-year-old age range?’ You go through those ... provisions that are already affecting the everyday lives of Americans, and people don’t want to get rid of them.”

But in a year when the national debate weighs so heavily on Virginia’s Senate race, both campaigns will need all the help they can get.

“If you see what my résumé is, and you understand my positions, and I’m still under 50 percent, then you’ve got to have people vote against your opponent to get over 50,” says Robert Denton, a professor at Virginia Tech specializing in political communications. “Both of them are in that situation. They’ve got to have a segment of the public vote against the other person.”